The present invention relates to an ink-jet printer for printing an image on a print medium with ink ejected from a print head, and more specifically to an ink supplement system for supplementing ink from a detachable ink bottle to an ink tank which stores ink to be supplied to the print head.
For example, Jpn. Pat. Appln. KOKAI Publication No. 10-138520 discloses a drum rotation ink-jet printer, which can make a large number of prints in a short period of time. The drum rotation ink-jet printer comprises a rotary drum which rotates in one direction and a print head for printing an image to a paper sheet wound around the rotary drum and rotating along with the drum. The print head has a plurality of ink-jet nozzles arranged in the axial direction of the rotary drum to extend across the paper sheet, and ejects ink from the ink-jet nozzles onto the paper sheet, which is moved relative to the print head by rotation of the rotary drum. Since this structure does not require considerable movement of the print head as in the conventional serial ink-jet printer, printing can be performed at high speed. Further, since ink is supplied to the print head from an ink tank of a large capacity located apart from the print head, the number of sheets printed for each supplementation of ink can be increased.
In the drum rotation ink-jet printer of the above-described type, the ink tank is located at a position remote from the printer head, and is used to supply ink to the print head. The ink tank has such a structure that an ink bottle filled up with reserve ink can be attached to and detached from the upper part of the tank. As the ink bottle is attached to the ink tank, ink is supplemented from the ink bottle to the ink tank until the surface of the ink liquid is leveled to a predetermined height.
The ink-jet nozzles described above are used to print extremely fine ink dots and therefore the print quality is deteriorated by dusts mixed in the ink and ink mist. In order to avoid such deterioration, a filter is interposed in an ink supply path provided between the ink tank and the print head in order to remove dusts mixed in the ink. Further, the ink supply path is designed in such a layout that the stagnation of ink, which cause ink mist, does not occur.
In the meantime, ink is manufactured by mixing a coloring additive to a main solvent, and therefore in some cases, the coloring additive remains in the ink as a fine particle after the ink is manufactured, or particle dusts are mixed into the ink while it is being manufactured. However, in the conventional ink-jet printer, a filter and an ink supply path do not have a structure of removing foreign matters such as fine particles of coloring additives and particle dusts. If such foreign matters are actually supplemented from the ink bottle to the ink tank, it is possible that the flow of ink is disturbed in the ink supply path and clogging of ink-jet nozzles occurs. Such drawbacks make it difficult to achieve printing of high-quality images at high speed.
Apart from the above, the conventional ink bottle easily falls out of the ink tank due to an external shock, which causes leaking of ink from the ink bottle. Such leaking of ink occurs also when the ink bottle is detached from the ink tank for replacement.
The present invention has been proposed as a solution to the above-described problems of the conventional technique, and the object thereof is to provide an ink supplement system capable of surely preventing ink containing foreign matters from being supplemented into the ink tank.
According to the present invention, there is provided an ink supplement system which comprises a bottle holder unit for holding an ink bottle storing ink and detachably attached thereto; and an ink tank for receiving ink from the ink bottle held by the bottle holder unit, wherein the ink bottle includes an ink supply port having a filter affixed to the back thereof and the bottle holder unit includes an ink supplement pump which suctions ink through the ink supply port of the ink bottle attached to the bottle holder unit so as to supplement the ink into the ink tank.
In the ink supplement system, the filter is affixed to the back of the ink supply port, and the ink supplement pump suctions ink through the ink supply port of the ink bottle attached to the bottle holder unit so as to supplement ink into the ink tank. Since the ink is forced to penetrate the filter by suction force of the ink supplement pump, the mesh of the filter can be made at a sufficiently fine pitch. Therefore, even if foreign matters such as fine particles of coloring additives and particle dusts are contained in the ink, the filter can reliably remove them from the ink to supplement it into the ink tank.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.